I personally think you'd have to pull the dash to get the dimmer switch out....it's freaking tight up in there. You might be able to get the plug off the back of the dimmer switch, check a wiring diagram & jump the wires to bypass the rheostat (dimmer) like TJP suggested.

You might want to double check the 3 amp fuse too which is on the far right of your fuse block. That runs the dash lights.